Mark hodgson



I imi ,51eme MARK' HoDesoN., or EAST SAGINAW, MICHIGANv Letters .Patent No. 105,942, dated August 2, 1870; antedated July 19, 1870.

@RATE-BAR.

WOP-

The Schedule referred to in these Letters Patent and making part ot the same.

To allwhom it may concern L Be it known that I, MARK HODGSON, of East Saginaw, in the county of Saginaw and State of Michigan, have inventeda new and useful Improvement in Grate- Bars, of which the following is a full, clear, and exact description, reference' being drawing forming part of this specification, and in Figure 1 represents a plan nf a gratebar constructed in accordance with my improvement;v

Figure 2, a longitudinal section of the same; and

Figure 3, a transverse section thereof.

Similar letters of reference indicate corresponding part-s. I

My invention relates to grate-bars, of arched or curvedform on their upper surface, and consists in a certain combination of cross-hars, of arched or curved form' on their tops, and set incluing, to favor a less thorough or abrupt break in the draught, with side supports, arrangedkto occupy a' lower position, and a central support level with the tops of the arches.

A grate-bar thus constructed will be found both durable and economical in its use, and possessesmany advantages over other constructions which form arched supports for the coal.l

In the accompanying drawing- A A represent the cross-bars, of arched or curved form on their upper surface, backward direction upward, as seen in fig. 2, leaving air and ash-spaces or openings a a between them.

This inclined direction of the cross-bars and their intermediate openings improves the draught, inasmuch as the same break or obstruction is .not'oered to the incoming airas'vcrtical openings, arranged be- -tween cross-bars set -to occupy a vertical position,

had to the accompanying and set inclining in a.

surfaces of the cross-hars,

described,

would present; also, such inclined posit-ion of said bars,l takenvin connection with their convex upper surface, does not oler the same facility for fine fuel to fall through the grate, unbnrnt, that bars of arched form at their topsfbut arranged to form vertical openings, do. l

These cross-'bats A A are supported at their: ends, on either side, by longitudinal bars echar-connecting surfaces B B, which, by their lower' position,"are free from destructive exposure by the fire, and serve to keep the cross-bars from warping and sagging, a centrai or intermediate vlongitudinal baror tie portion or portions, O C, also serving to thus protect and stitfen the cross-bars A A, and,-by arranging such central bar to lie on a level at its top with the upper surfaces of the'arches or cross-bars, provision is alorded for work- Ling a clnker-bar over the grate to clear it, and that otherwise it would be difficult or impractoable to do.

What is here claimed, and desired to be secured by Letters Patent, is-

1. A grate-bar, composed of suitably-supported cross-bars A A, set to occupy an inclined position, as described, and of curved or arched form on their tops, substantially as specified.

2. The combination of the inclined cross-bars A A, of curvedl or arched form on their upper surfaces, the longitudinal side bars or portions' B B, and the centrai longitudinal tie-barorportions C C, arranged to extend upward, so as to lie on a level with the upper essentially as shown and MARK HODGsoN. Witnessesz' ALFRED W. N Ewros. lnvme M. SMITH. 

